Comparison of gut toxicity and microbiome effects in zebrafish exposed to polypropylene microplastics: Interesting effects of UV-weathering on microbiome.

Weathered microplastics (MPs) exhibit different physicochemical properties compared to pristine MPs, thus, their effects on the environment and living organisms may also differ. In the present study, we investigated the gut-toxic effects of virgin polypropylene MPs (PP) and UV-weathered PP MPs (UV-PP) on zebrafish. The zebrafish were exposed to the two types of PP MPs at a concentration of 50 mg/L each for 14 days. After exposure, MPs accumulated primarily within the gastrointestinal tract, with UV-PP exhibiting a higher accumulation than PP. The ingestion of PP and UV-PP induced gut damage in zebrafish and increased the gene expression and levels of enzymes related to oxidative stress and inflammation, with no significant differences between the two MPs. Analysis of the microbial community confirmed alterations in the abundance and diversity of zebrafish gut microorganisms in the PP and UV-PP groups, with more pronounced changes in the PP-exposed group. Moreover, the Kyoto Encyclopedia of Genes and Genomes pathway analysis confirmed the association between changes in the gut microorganisms at the phylum and genus levels with cellular responses, such as oxidative stress, inflammation, and tissue damage. This study provides valuable insights regarding the environmental impact of MPs on organisms.

Attention-Based Bi-Prediction Network for Versatile Video Coding (VVC) over 5G Network.

As the demands of various network-dependent services such as Internet of things (IoT) applications, autonomous driving, and augmented and virtual reality (AR/VR) increase, the fifthgeneration (5G) network is expected to become a key communication technology. The latest video coding standard, versatile video coding (VVC), can contribute to providing high-quality services by achieving superior compression performance. In video coding, inter bi-prediction serves to improve the coding efficiency significantly by producing a precise fused prediction block. Although block-wise methods, such as bi-prediction with CU-level weight (BCW), are applied in VVC, it is still difficult for the linear fusion-based strategy to represent diverse pixel variations inside a block. In addition, a pixel-wise method called bi-directional optical flow (BDOF) has been proposed to refine bi-prediction block. However, the non-linear optical flow equation in BDOF mode is applied under assumptions, so this method is still unable to accurately compensate various kinds of bi-prediction blocks. In this paper, we propose an attention-based bi-prediction network (ABPN) to substitute for the whole existing bi-prediction methods. The proposed ABPN is designed to learn efficient representations of the fused features by utilizing an attention mechanism. Furthermore, the knowledge distillation (KD)- based approach is employed to compress the size of the proposed network while keeping comparable output as the large model. The proposed ABPN is integrated into the VTM-11.0 NNVC-1.0 standard reference software. When compared with VTM anchor, it is verified that the BD-rate reduction of the lightweighted ABPN can be up to 5.89% and 4.91% on Y component under random access (RA) and low delay B (LDB), respectively.

Impacts of the COVID-19 lockdown in China on new particle formation and particle number size distribution in three regional background sites in Asian continental outflow.

Despite the curtailment of atmospheric condensing precursor gases during the Coronavirus disease 2019 (COVID-19) lockdown (LD) period, unexpected haze events via the formation of new particles and their subsequent growth have been identified. This study investigated the impact of emission reduction during the Chinese LD period on the new particle formation (NPF) frequency and corresponding particle number size distribution (PNSD) at three regional background atmospheric monitoring sites in the western coastal areas of the Korean Peninsula. During this duration, the number concentrations of the nucleation- (<25 nm) and accumulation-mode (>90 nm) particles significantly decreased in Baengryeong (BRY), showing decreases of 34% and 29%, respectively. Unlike BRY, the PNSD in Anmyeon (AMY), which is influenced by nearby industrial emissions, remained nearly unchanged during the LD period, possibly because the reduction in industrial emissions was not significant during the social distancing period enforced by Korea. Bongseong (BOS) showed a similar variation to that of BRY; however, the magnitude of the reduction was weaker because of its higher altitude compared to other sites. The cyclostationary empirical orthogonal function technique was applied to the measured PNSDs at the three sites to objectively classify NPF events. Because mode 1 of cyclostationary loading vectors commonly represented the typical diurnal variation of PNSD during regional NPF events at three sites, mode 1 of the corresponding principal component time series was used for NPF classification. The NPF frequency decreased by 7%, 1%, and 7% in BRY, AMY, and BOS, respectively, despite favorable meteorological conditions, such as increased temperature and insolation during the LD period. The diurnal variation in the sulfuric acid (H2SO4) proxy implied that the H2SO4 proxy acted as a determining factor for NPF events during the NPF occurrence time (8-12 local hours) in AMY and BOS; however, NPF occurrence in BRY was not connected to the H2SO4 proxy level. This suggests that BRY was more likely to be influenced by the reduction in organic species in the continental upwind regions, while the occurrence of NPF events in AMY and BOS can be suppressed in association with the distinct reduction in inorganic compounds represented by the H2SO4 proxy during the LD period.

Chronic effects of nano and microplastics on reproduction and development of marine copepod Tigriopus japonicus.

This study aimed to examine the impact of chronic (30 days) exposure to polystyrene microplastics (PS-MPs) of different sizes (50 nm and 2 µm) and at different concentrations (0.5 µg/L and 100 mg/L) to marine copepod Tigriopus japonicus. Polystyrene microplastics affected survival rates in size- and concentration-dependent manners. The LC50s values of 50 nm and 2 µm PS-MPs were 0.10 mg/L and 3.92 mg/L, respectively. The developmental time was delayed by 50 nm PS-MPs, and Usp expression was downregulated. Reproduction was negatively affected by 2 µm PS-MPs even at environmentally relevant concentrations; however, the expression of Vtg was not altered. The production rates of reactive oxygen species and nitric oxide also increased after exposure to PS-MPs; but this effect was independent of particle size. The expression levels of Cat and Tnf, genes related to oxidative stress and inflammation, respectively, were upregulated by exposure to PS-MPs, independently of particle size. Meanwhile, the level of oxidative stress in T. japonicus was not significantly affected by PS-MPs at environmentally relevant concentrations. This study suggests that nano-sized PS-MPs are not always more toxic than micro-sized PS-MPs, and that oxidative stress is a key factor in determining the toxic effect on T. japonicus at high concentrations.

Long-term exposure of the Mediterranean mussels, Mytilus galloprovincialis to polyethylene terephthalate microfibers: Implication for reproductive and neurotoxic effects.

As one of major types of microplastics (MPs), microfibers (MFs) are widely found in the marine ecosystem and can induce diverse impacts on various marine organisms. Sedentary species, such as mussels, can act as bioindicators for monitoring marine contamination. Hence, in this study, we used mussels (Mytilus galloprovincialis) to examine the toxicity of polyethylene terephthalate (PET) MFs of 100 µm size at concentrations of 0.0005, 0.1, 1, 10, and 100 mg/L for 32 days. PET MFs accumulated only in the stomachs and intestines of the mussels and caused digestive tubule atrophy. After exposure to PET MFs, no alteration in the mortality rate, shell height, length, and weight of the mussels was observed. However, the gonadal index decreased with increasing concentrations of PET MFs. This is because PET MFs decrease the sex hormones estradiol and testosterone in mussels, even at environmentally relevant concentrations. Furthermore, chronic exposure to PET MFs increased the activities of antioxidant-related (catalase and superoxide dismutase) and neurotoxicity-related (acetylcholine esterase) enzymes in the digestive gland and gill tissues of mussels. In addition, cellular immune parameters of apoptosis and DNA damage were observed in mussel hemocytes. Thus, this study demonstrates the risks of MPs in real marine environments by assessing how long-term exposure to low concentrations of PET MFs can cause potential sublethal impacts and reproductive failure in mussels.

The Korea-United States Air Quality (KORUS-AQ) field study.

The Korea-United States Air Quality (KORUS-AQ) field study was conducted during May-June 2016. The effort was jointly sponsored by the National Institute of Environmental Research of South Korea and the National Aeronautics and Space Administration of the United States. KORUS-AQ offered an unprecedented, multi-perspective view of air quality conditions in South Korea by employing observations from three aircraft, an extensive ground-based network, and three ships along with an array of air quality forecast models. Information gathered during the study is contributing to an improved understanding of the factors controlling air quality in South Korea. The study also provided a valuable test bed for future air quality-observing strategies involving geostationary satellite instruments being launched by both countries to examine air quality throughout the day over Asia and North America. This article presents details on the KORUS-AQ observational assets, study execution, data products, and air quality conditions observed during the study. High-level findings from companion papers in this special issue are also summarized and discussed in relation to the factors controlling fine particle and ozone pollution, current emissions and source apportionment, and expectations for the role of satellite observations in the future. Resulting policy recommendations and advice regarding plans going forward are summarized. These results provide an important update to early feedback previously provided in a Rapid Science Synthesis Report produced for South Korean policy makers in 2017 and form the basis for the Final Science Synthesis Report delivered in 2020.

Impact of polyethylene terephthalate microfiber length on cellular responses in the Mediterranean mussel Mytilus galloprovincialis.

Many studies have investigated the toxic effects of microplastics in marine organisms, but most studied nano-sized round microplastics at high concentrations and were not environmentally relevant. To understand the cellular toxicity of polyethylene terephthalate microfibers (PET-MFs) by length (50 and 100 µm), Mediterranean mussels (Mytilus galloprovincialis) were exposed to environmental (0.5 µg/L) and high (100 mg/L) MF concentrations for four days. Short PET-MFs accumulated in the lower intestinal organs of the mussels, but long PET-MFs were only observed in the upper intestinal organs. Both sized PET-MFs affected necrosis, DNA damage, reactive oxygen species, nitric oxide, and acetylcholinesterase (AChE) activity. Significant MF length-dependent effects occurred at environmentally relevant concentrations for DNA damage (100 µm MFs) and AChE activity (50 µm MFs). However, length effects disappeared at the higher exposure concentration. The current study provides potentially sensitive indicators to detect MFs exposure and the ecotoxicological implications of MFs in marine ecosystems.

Evaluation of microplastic toxicity in accordance with different sizes and exposure times in the marine copepod Tigriopus japonicus.

The indiscriminate use of plastic has greatly increased microplastic contamination risk in the marine environment. Microplastics can affect all marine life via the food web, from primary producers (e.g., microalgae) to final consumers (e.g., carnivorous fish). Thus, several studies have attempted to evaluate microplastic toxicity, but information about the underlying mechanisms of their effect is limited. Therefore, in this study, we examined multiple factors that could contribute to microplastic-induced toxicity. We investigated the potential molecular effects of microplastic size and exposure time. We exposed the marine copepod Tigriopus japonicus to 50 nm and 10 µm polystyrene microbeads. We found that both size and exposure time increased intracellular levels of reactive oxygen species. In addition, antioxidant-related gene expression was modulated and antioxidant enzyme activities were changed significantly. The results of this study provide important insights into the molecular mechanisms of microplastic-induced toxicity in a marine organism.

Toxicological effects of irregularly shaped and spherical microplastics in a marine teleost, the sheepshead minnow (Cyprinodon variegatus).

The increasing global contamination of plastics in marine environments is raising public concerns about the potential hazards of microplastics to environmental and human health. Microplastics formed by the breakdown of larger plastics are typically irregular in shape. The objective of this study was to compare the effects of spherical or irregular shapes of microplastics on changes in organ distribution, swimming behaviors, gene expression, and enzyme activities in sheepshead minnow (Cyprinodon variegatus). Both types of microplastics accumulated in the digestive system, causing intestinal distention. However, when compared to spherical microplastics, irregular microplastics decreased swimming behavior (i.e., total distance travelled and maximum velocity) of sheepshead minnow. Both microplastics generated cellular reactive oxygen species (ROS), while ROS-related molecular changes (i.e., transcriptional and enzymatic characteristics) differed. This study provides toxicological insights into the impacts of environmentally relevant (fragmented) microplastics on fish and improves our understanding of the environmental effects of microplastics in the ecosystem.

Comparative Analysis of Transcriptional Profile Changes in Larval Zebrafish Exposed to Zinc Oxide Nanoparticles and Zinc Sulfate.

Many studies of the toxic effects of zinc oxide nanoparticles (ZnO NPs) in aquatic organisms have been performed because of increasing ZnO NP use. However, the toxicological pathways are not understood. In this study, ZnO NPs were found to be more toxic than ZnSO4 to zebrafish larvae, but ZnO NP toxicity did not involve transcript alterations. Biological processes affected by ZnO NPs and ZnSO4 were investigated by performing ingenuity pathway analysis on differently expressed genes in larvae exposed to sub-lethal ZnO NP and ZnSO4 concentrations. We identified upregulated and downregulated differently expressed genes in fish exposed to ZnO NPs and ZnSO4, and found that ZnO NPs slightly induced cell differentiation and pathways associated with the immune system and activated several key genes involved in cancer cell signaling. The results may be key to predicting and elucidating the mechanisms involved in ZnO NP and ZnSO4 toxicity in zebrafish larvae.

Differentially transcriptional regulation on cell cycle pathway by silver nanoparticles from ionic silver in larval zebrafish (Danio rerio).

Silver nanoparticles (AgNPs) have a strong antibacterial activity and the relevant modes of actions have regarded as direct or indirect causes of toxicity observed in the environment. In this study, the transcriptomic profiles in larval zebrafish (Danio rerio) exposed to AgNPs (about 50 nm in size) and AgNO3 as a comparative ionic silver were investigated and analyzed using differential expressed gene (DEG), Gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) pathway analyses. Results indicated that underlying molecular mechanisms are different each other. Interestingly, the global gene expression profiling showed that cell cycle pathway is affected by both AgNPs and dissolved Ag+, however its regulation pattern was opposite each other. To the best of our knowledge, the up-regulation of cell cycle pathway by AgNPs and down-regulation by Ag+ is the first reporting and suggests the distinguished toxicological perspective from a well-known hypothesis that Ag+ mainly regulates the cell cycle. This study provides novel insights onto the genotoxicological mechanisms of AgNPs.

Developmental Toxicity of Zinc Oxide Nanoparticles to Zebrafish (Danio rerio): A Transcriptomic Analysis.

Zinc oxide nanoparticles (ZnO NPs) are being utilized in an increasing number of fields and commercial applications. While their general toxicity and associated oxidative stress have been extensively studied, the toxicological pathways that they induce in developmental stages are still largely unknown. In this study, the developmental toxicity of ZnO NPs to embryonic/larval zebrafish was investigated. The transcriptional expression profiles induced by ZnO NPs were also investigated to ascertain novel genomic responses related to their specific toxicity pathway. Zebrafish embryos were exposed to 0.01, 0.1, 1, and 10 mg/L ZnO NPs for 96 h post-fertilization. The toxicity of ZnO NPs, based on their Zn concentration, was quite similar to that in embryonic/larval zebrafish exposed to corresponding ZnSO4 concentrations. Pericardial edema and yolk-sac edema were the principal malformations induced by ZnO NPs. Gene-expression profiling using microarrays demonstrated 689 genes that were differentially regulated (fold change >1.5) following exposure to ZnO NPs (498 upregulated, 191 downregulated). Several genes that were differentially regulated following ZnO NP exposure shared similar biological pathways with those observed with ZnSO4 exposure, but six genes (aicda, cyb5d1, edar, intl2, ogfrl2 and tnfsf13b) associated with inflammation and the immune system responded specifically to ZnO NPs (either in the opposite direction or were unchanged in ZnSO4 exposure). Real-time reverse-transcription quantitative polymerase chain reaction confirmed that the responses of these genes to ZnO NPs were significantly different from their response to ZnSO4 exposure. ZnO NPs may affect genes related to inflammation and the immune system, resulting in yolk-sac edema and pericardia edema in embryonic/larval developmental stages. These results will assist in elucidating the mechanisms of toxicity of ZnO NPs during development of zebrafish.

Transcriptional changes in steroidogenesis by perfluoroalkyl acids (PFOA and PFOS) regulate the synthesis of sex hormones in H295R cells.

Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) are two of the most widely used perfluoroalkyl acids (PFAAs). Because of their strong persistence, they have become widely distributed throughout the environment and human bodies. PFOA and PFOS are suspected to disrupt the endocrine system based upon many in vivo studies, but the underlying mechanisms are currently unclear. In this study, we investigated the endocrine-related effects of PFOA and PFOS using in vitro estrogen receptor (ER) and androgen receptor (AR) transactivation assays and steroidogenesis assay. The results showed that PFOA and PFOS exhibited weak antagonistic ER transactivation but did not exhibit agonistic ER or AR transactivation. In the steroidogenesis assay, PFOA and PFOS induced 17ß-estradiol (E2) level and reduced testosterone level, which would be caused by the induction of aromatase activity. The qPCR analysis of genes involved in steroidogenesis indicates that PFOA and PFOS associate with sex hormone synthesis by the transcriptional induction of two genes, cyp19 and 3ß-hsd2. Moreover, the transcriptional induction of cyp11b2 by PFOS suggests that this chemical may underlie the disruption of several physiological functions related to aldosterone. The results of the current study suggest that PFOA and PFOS are potential endocrine disrupting chemicals (EDCs) and provide information for further studies on the molecular events that initiate the adverse endocrine effects.

Effects of combination therapy of statin and N-acetylcysteine for the prevention of contrast-induced nephropathy in patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention.

BACKGROUND: Acute myocardial infarction (AMI) is a risk factor for contrast-induced nephropathy (CIN). We investigated whether pretreatment with statin, N-acetylcysteine (NAC) and sodium bicarbonate (NaHCO3) reduces the risk of CIN. METHODS: We conducted a prospective trial and enrolled a total of 334 ST-segment elevation myocardial infarction (STEMI) patients. Patients were divided into four groups: Group I (statin 40mg), Group II (statin 80mg), Group III (statin 80mg plus NAC 1200mg) and Group IV (regimen of group III plus NaHCO3 154mEq/L). CIN was defined as ≥25% or ≥0.5mg/dL increase in serum creatinine from the baseline within the 72h after PCI. RESULTS: CIN occurred in 72 (21.6%) patients. The incidence of CIN was the lowest in the group III (14.3%), and multivariate analysis showed the lower incidence of CIN in group III compared to Group I [odds ratio (OR) 0.29, 95% confidence interval (CI) 0.13-0.64, p=0.002]. Admission hyperglycemia [(AHG)>198mg/dL] (OR 2.20, 95% Cl 1.20-3.68, p=0.011) and the use of intra-aortic balloon pump (IABP) (OR 4.20, 95% CI 1.38-12.78, p=0.016) were independent predictors for CIN. The CIN (OR 9.00, 95% CI 1.30-62.06, p=0.026) was an independent predictor for in-hospital mortality. CONCLUSIONS: Combination of high-dose statin plus NAC was associated with lower incidence of CIN in patients with STEMI who underwent primary PCI compared to statin only.

Efficient recovery of nitrate and phosphate from wastewater by an amine-grafted adsorbent for cyanobacterial biomass production.

Various types of wastewater have been widely utilized in microalgae and cyanobacteria cultivation for environmental and economic reasons. However, the problems of low cell growth and biomass contamination due to direct use of wastewater remain unresolved. In the present study, nitrate and phosphate were separated from wastewater by adsorption and subsequently used for cyanobacterial biomass production. To this end, an amine-grafted magnetic absorbent was synthesized. The synthesized absorbent recovered ca. 78% nitrate and 93% phosphate from wastewater. Regenerated medium was prepared using recovered nutrients as nitrogen and phosphate sources, which were efficiently assimilated by cyanobacterial culture. Compared to synthetic medium, there was no difference in growth and nutrient removal using regenerated medium. The proposed indirect method of wastewater utilization would prevent contamination of the produced biomass by unfavorable substances, which will broaden its potential applications.

Estrogenic potency of bisphenol S, polyethersulfone and their metabolites generated by the rat liver S9 fractions on a MVLN cell using a luciferase reporter gene assay.

BACKGROUND: Bisphenol A (BPA) is an applied chemical that is used in many industrial fields and is a potential endocrine disruption chemical (EDC) that is found in the environment. Bisphenol S (BPS) and polyethersulfone (PES) have been suggested as putative BPA alternatives. In this study, the estrogenic potency induced by the binding of 17-beta-estradiol (E2), BPA, BPS, PES and their metabolites formed by the rat liver S9 fraction to the human estrogen receptor (ER) was estimated. METHODS: We used an in vitro bioassay based on the luciferase reporter assay in MVLN cells to evaluate the estrogenic activity of 17-beta-estradiol (E2), BPA, BPS, PES (E2: 0.001 to 0.3 nM; BPA, BPS and PES: 0.0001 to 5 microM) and their metabolites (E2: 0.05 microM; BPA, BPS and PES: 0.1 mM) according to incubation times (0, 20 and 40 min). After chemical treatment to MVLN cells for 72 hrs, and the cell viability and luciferase intensity induced were estimated, from which the estrogenic activity of the chemicals tested was evaluated. RESULTS: BPA and BPS induced estrogenic activity whereas PES did not show any estrogenic activity in the concentrations tested. In an in vitro assay of metabolites, BPA metabolites displayed comparable estrogenic activity with BPA and metabolites of both BPS and PES showed increasing estrogenic activity. CONCLUSIONS: The results suggest that the metabolites of BPS and PES have estrogenic potential and the need for the assessment of both chemicals and their metabolites in other EDC evaluation studies. The estrogenic potency of PES and its metabolites is the first report in our best knowledge.

The association of socioeconomic status with three-year clinical outcomes in patients with acute myocardial infarction who underwent percutaneous coronary intervention.

The aim of this study was to evaluate whether the clinical outcomes were associated with socioeconomic status (SES) in patients with acute myocardial infarction (AMI) who underwent percutaneous coronary intervention (PCI). The author analyzed 2,358 patients (64.9 ± 12.3 yr old, 71.5% male) hospitalized with AMI between November 2005 and June 2010. SES was measured by the self-reported education (years of schooling), the residential address (social deprivation index), and the national health insurance status (medical aid beneficiaries). Sequential multivariable modeling assessed the relationship of SES factors with 3-yr major adverse cardiovascular events (MACEs) and mortality after the adjustment for demographic and clinical factors. During the 3-yr follow-up, 630 (26.7%) MACEs and 322 (13.7%) all-cause deaths occurred in 2,358 patients. In multivariate Cox proportional hazards regression modeling, the only lower education of SES variables was associated with MACEs (hazard ratio [HR], 1.41; 95% confidence interval [CI], 1.04-1.91) and mortality (HR, 1.93; 95% CI, 1.16-3.20) in the patients with AMI who underwent PCI. The study results indicate that the lower education is a significant associated factor to increased poor clinical outcomes in patients with AMI who underwent PCI.

Deoxyribonucleic Acid copy number aberrations in vasospastic angina patients using an array comparative genomic hybridization.

BACKGROUND AND OBJECTIVES: Vasospastic angina (VA) is a specific type of coronary artery disease and develops as a result of coronary artery spasm. Recently, a few studies have revealed that VA caused by coronary artery spasm is related to genetic traits. The objective of this study was to use the recently developed technique of array comparative genomic hybridization (CGH) to screen the genetic aberrations of VA. SUBJECTS AND METHODS: To identify candidate genes that might be causally involved in the pathogenesis of VA, genomic deoxyribonucleic acids were extracted from whole blood of 28 patients with VA who presented at Department of Cardiology at Seoul St. Mary's Hospital, Seoul, Korea. The copy number profiles of these patients was then analyzed using array CGH and reverse transcriptase (RT) quantitative polymerase chain reaction (PCR). RESULTS: Array CGH revealed gains in 31 different regions, with losses in the 4q35.2, 7q22.1, 10q26.3, 15q11.2, 16p13.11, 17p11.2 and 19q13.3 regions (more than 32% aberration in these regions). Several loci were found to be frequently including gains of 5p and 11q (50% of samples). The most common losses were found in 7q (54% of samples). Copy number aberrations in chromosomal regions were detected and corresponding genes were confirmed by RT quantitative PCR. The fold change levels were highest in the CTDP1 (18q23), HDAC10 (22q13.33), KCNQ1 (11p15.5-p15.4), NINJ2 (12p13.33), NOTCH2 (1p12-p11.2), PCSK6 (15q26.3), SDHA (5p15.33), and MUC17 (7q22.1) genes. CONCLUSION: Many candidate chromosomal regions that might be related to the pathogenesis of VA were detected by array CGH and should be systematically investigated to establish the causative and specific genes for VA.

Permanent ulnar nerve palsy after embolotherapy of arteriovenous malformation around the elbow.

Permanent nerve palsy is an extremely rare but critical complication after embolotherapy of arteriovenous malformations of the extremities. The authors present a case of permanent ulnar nerve palsy after embolotherapy of an arteriovenous malformation around the elbow, and caution that transcatheter embolotherapy of arteriovenous malformations located close to major neurovascular structures must be carefully planned and individualized.

Genetic traits of avascular necrosis of the femoral head analyzed by array comparative genomic hybridization and real-time polymerase chain reaction.

In an attempt to observe the genetic traits of avascular necrosis of the femoral head, we analyzed the genomic alterations in blood samples of 18 patients with avascular necrosis of the femoral head (9 idiopathic and 9 alcoholic cases) using the array comparative genomic hybridization method and real-time polymerase chain reaction. Several candidate genes were identified that may induce avascular necrosis of the femoral head, and we investigated their role in the pathomechanism of osteonecrosis of bone. The frequency of each candidate gene over all the categories of avascular necrosis of the femoral head was also calculated by real-time polymerase chain reaction. The highest frequency specific genes in each category were FLJ40296, CYP27C1, and CTDP1. FLJ40296 and CYP27C1 had the highest frequency (55.6%) in the idiopathic category. FLJ40296 had a high frequency (44.4%) in the alcoholic category, but CYP27C1 had a relatively low frequency (33.3%) in the alcoholic category. However, CTDP1 showed a significantly high frequency (55.6%) in the alcoholic category and a low frequency (22.2%) in the idiopathic category. Although we statistically analyzed the frequency of each gene with Fisher's exact test, we could not prove statistical significance due to the small number of samples. Further studies are needed with larger sample numbers. If the causal genes of avascular necrosis of the femoral head are found, they may be used for early detection, prognosis prediction, and genomic treatment of avascular necrosis of the femoral head in the future.